Facebook founder Mark Zuckerbeg went back to Harvard on Thursday to deliver the commencement address and to get his degree 11 years after he dropped out to start the world's biggest social media company.

At 33, Zuckerberg becomes the youngest commencement speaker ever at Harvard and only the second drop out - the first was Bill Gates.

His wife Priscilla Chan and the class of 2017 listened in the rain as Zuckerberg delivered his message - if you create opportunities, you create purpose.

Not just for yourself, but for others.

"Let's give everyone the freedom to pursue purpose. We're all better for it," he said.

Zuckerberg's speech may have been well-received but not Facebook's live-captioning.